EDIT: It was probably not a smart move to post this question in here, but maybe nevertheless someone could briefly clarify how GPS_AUTO_SWITCH = 0 is supposed to behave in a dual GPS setup. THX
I would have a question as regards the working of GPS_AUTO_SWITCH.
I'm using AC3.5-rc9, and have a main gps on the uart, as usual, and a second gps on uavcan.
The 2nd gps is a DIY uavcan gps, which I want to first test before I start relying on in it in flights. I thought that a proper strategy would be to set GPS_AUTO_SWITCH = 0, hoping that this way the flight would be totally based on only the main gps, as it usually would be, but that the data of the 2nd gps is logged and thus can be analyzed.
So, as a precursor, I did a simple test today, where I had the system just sitting in the outside for a while. The following was reproducible 4 times.
The main gps took quite longer for finding a fix than the 2nd gps, but the MissionPlanner HUD displayed a 3D-Fix at the moment the 2nd gps went good, even though the main gps still showed a hdop of 99.99!
I could capture that on a log: http://www.olliw.eu/drop/apm/1980-01-06-00-59-43.bin
I don't understand this behavior. I would have expected that with GPS_AUTO_SWITCH = 0 the 3D-Fix is based on the main gps. The EKF at least seems to. So, I'm somewhat unsure as regards what that would mean for a real flight. Is it safe to fly, when the 3D-Fix is displayed, even though the main gps is still at hdop 99.99?